Tuesday, November 8, 2011

How to use Liferay third-party libraries as Maven dependencies ?

Almost all day worth of work but finally I finished DependencyInstallerMojo. Simply put, you provide it with destination of Liferay's lib/versions.xml and inclusion regexp patterns that determine which libraries are to be installed into either local maven repository or a custom location and it installs them as Maven artifacts and generates a pom definition that contains corresponding dependencies, so that you can use itself as dependency and thus transitively include all those libraries on your classpath.

  
 <plugin>
    <groupId>com.liferay.maven.plugins</groupId>
    <artifactId>liferay-maven-plugin</artifactId>
    <version>6.1.0-SNAPSHOT</version>
    <configuration>
      <generatedPomLocation>${project.basedir}/target/generated-pom.xml</generatedPomLocation>
      <generatedPomVersion>${project.version}</generatedPomVersion>
      <generatedPomName>Liferay dependencies</generatedPomName>
      <localRepositoryId>liferay-third-party-deps</localRepositoryId>
      <projArtifactId>${project.artifactId}</projArtifactId>
      <projGroupId>${project.groupId}</projGroupId>
      <dependencyScope>test</dependencyScope>
      <libDirPath>/opt/liferay/portal/lib</libDirPath>
      <localRepositoryPath>/home/old-lisak/fake-repo</localRepositoryPath>
      <include>
        <development>jsf-.*,derby,catalina,ant-.*,jalopy</development>
        <global>portlet.jar</global>
        <portal>chemistry-.*,commons-.*,jackrabbit-.*,spring-.*</portal>
      </include>
    </configuration>
 </plugin>

Most of those properties are set by default, you actually need to set at least :
 libDirPath - to the source xml file (versions.xml in case of Liferay)
 localRepositoryPath - to a custom local maven repository, unless you want to use the default one
 include - this element is a map of sub-directories of libDirPath that contains jar packages

Names of the sub-directories become part of groupId (com.example.development) and regular expressions adhere to java.util.regex split up by colons.


Why Liferay developers might need this ?


Because if you wanted your code to be covered by infrastructure tests, you would have to mock Liferay services quite frequently, unless you have Liferay third party libraries on classpath and you can boot up the spring based infrastructure and  hundreds of its services.
   Mocking might seem to be a suitable alternative until you are refactoring or upgrading Liferay version and all those tests turn into a maintenance hell. I personally use rather infrastructure testing than tons of "functional" unit tests, so that I'm trying to deal with this situation.

A year ago I manually listed maven dependencies corresponding to those listed in lib/versions.xml, just those that I needed for using particular Liferay services, but it is a really hideous thing to do because of all those version conflicts and transitive dependencies.

I wrote this Maven Mojo after I got really repelled by Maven Surefire Plugin's way of dealing with additional classpath resources, classloading hell.

A last possible option how to do this is systemPath property of Maven Dependency of system scope, but it is deprecated and it will be probably not supported in next releases.

If you want to try that out, follow these instructions :

$git clone git@github.com:l15k4/liferay-maven-support.git
$cd liferay-maven-support
$mvn install

Then go into an existing maven project and add this plugin into its build section.

  
 <plugin>
   <groupId>com.liferay.maven.plugins</groupId>
   <artifactId>liferay-maven-plugin</artifactId>
   <version>6.1.0-SNAPSHOT</version>
   <configuration>
     <libDirPath>/path/to/portal/lib</libDirPath>
     <localRepositoryPath>/home/user/test-maven-repository</localRepositoryPath>
     <include>
       <development>jsf-.*,derby,catalina,ant-.*,jalopy</development>
       <global>portlet.jar</global>
       <portal>chemistry-.*,commons-.*,jackrabbit-.*,spring-.*</portal>
     </include>
   </configuration>
 </plugin>

$mkdir /home/user/test-maven-repository
$mvn com.liferay.maven.plugins:liferay-maven-plugin:6.1.0-SNAPSHOT:install-dependencies


If everything goes well, the repository will contain the artifacts and there will be target/generated-pom.xml file in your project.

If you found this useful and you wanted to see this as part of liferay-maven-plugin, you could vote up here: LSP-22947

1 comment:

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